Swinging scaffold



Apil 1, 19244 1,488,822 l R. J. LACKNER SWINGING SCAFFOLD Filed Jan. 1'7 1923 2 Sheets-Sheet 1 Mln.

- 'Ro Lac/Pez- .April '1 11924. 1,488,822

'R. J. LA CKNER SWINGING SCAFFOLD Filed Jan. 17,; 1923 2 Sheets-Sheet"2 wuwstoz (nu, euhm@ Patented Apr. 1, 1924.

UNITED STATE-s PATENT lorries,

ROLPH J. nAoKNEa, or NEW YORK, N. Y, AssiGNoR To LACKNER PRODUCTS oon- PORATION, OF BROOKLYN, NEW Yon-K, A CORPORATION or DELAWARE.

SWINGING SGAFFOLD.

Application filed January 17, 1923. Serial No. 613,174. f

T all 'whom t may concern:

Be it known that I, ROLPH J. LAokNnn, a citizen of the United States, residing in the city of New York and State of New York` have invented certain new and useful 1mprovements in Swinging Soafolds, of which the following is a specification.

The object of the present invention is to provide means whereby, if the suspending rope at either end of a swinging scaffold should break at any point, the remaining strands of the rope will be automatically and positively clamped so that dropping of the scaffold will be prevented. The invention seeks to provide means for the stated purpose which may be easily applied to any swinging scaffold and adjusted to the size of the same and to the number of strands or runs in the suspending rope. The invention further seeks to provide means for the stated purpose which will be simple inthe construction and arrangement of lthe several parts and which will not interfere in any way with the usual manipulation of the scaffold. The invention is illustrated in the accompanying drawings and will be hereinafter fully set forth.

In the drawings-- Figure 1 is a side elevation of a swinging scaffold equipped with my improvei'nents, some of the parts being broken away;

Fig. 2 is 4an elevation of one end of the scaffold showing my improved safety device in the'position assumed to prevent dropping of the scaffold after the suspending rope breaks, and

Fig. 8 is a top planv view' ofthe safety deL vice with the suspending ropesin section.

The scaffold consists of a-floor 1 carried by rungs 2 between side rails 3 ofthe usual form; Hanger irons t are' engaged around the end portions ofthescadold platform and are constructedv at their upper ends with eyes '5 to beengaged by hooks 6 on the lower pulley blocks 7, theseh'anger irons being also provided witheyes or loops 8 on their outer sides to receive the usual guard rail 9. The suspendingrope lOis traiiied'back andV forth between the pulley block 7 andthe upper pulley block 10 in the ,usual `manner and the' upper pulley block isV equipped with a hook 11 engagedY in a: suspending bracket which is' anchored upon the roof in the usual" manner.

ln carrying'out my invention, I secure to the ropeanchoring structure 13, upon the upperend of the lower pulley block 7, a bracket or post 14 which rises above said a'nchoring structure and has a lever 15 pivota-lly attached to its upper end. Below the pivot bolt 16 which connects the post la with the lever 15, a pivot bolt 17 is inserted through a suitable' lug or ear on the said post and' through the fork 18 ext-ending outwardly from a clampingjaw 19 whereby to` pivotally connect said jaw to said post, it being understood that the rear end of the level` 15 is also forked, as shown at 20, so that the upper end ofthe supporting'post or bracket 14 will be disposed betweenk inembers of the lever and of the clamping and' lateral or twisting movement of the lever or the jaw relative to the said support will be prevented. At the outer side of the supporting post 14, a link 21 is extended between the extremities of the fork 18 and the fork 2O so as to form a hinge connectionv between said members and relieve the strain upon the supporting post. The lever 15a extends outwardly to a point nearly or quite inthe vertical plane of the outermost rung 2 of the scaffold, and its outer extremity is bifurcated, as shown at 22, to receive the upper end of a connecting rod 23, the upper end of said rod' being flattened',5as shown at 24, and provided' with a longitudinally extending series of openings 25 therethrough whereby the attaching bolt 26 may be disposed at any desired point inv the length of the connecting rod and vary the effective length of said rod' and the throw of thev lever according to the demands of any Aparticular scaffold andthe weight imposed upon it. The lower end of the' con'- nect'ing rod 23 is constructed withan eye 27 to receive a pivot bolt 28, which` bolt also passes through' lugs 29 on the upper sideV of a clamping plate 80.' The clamping plate 30 rests upon the floor 1 immediately over the end'- ruIiOl 2 and a bowed clampingv plate 51 is' disposed againsty the under side of the said rung andin engagement therewith and connected withatheupper clamping plate SOby bolt-s 82 inserted througlrthe ends of the said plates at opposite sides of the rung, asclearly shown in Fig. 1, thereby securely anchoring the connecting rod to the endl of the scaffold. Yivotally attached to the lever loand arranged to cO-operate with the jaw 19i`s a second jaw 33 which is arranged at' the opposed at 'opposite sides ofthe lever 15 and' pivotally attached thereto, as will be lreadily understood. In the outer end ofthe arm 34 is inounted a setgboltw''fwhich bears against the under edge of the lever l5 and which fniay be adjusted in an obvious vinan-` ner'to swing'the arm 3e about its pivotal connectionxwith the Alever so that the awY 33 willbe set-'closer to or'farther from the'suse pendingfropeLI The jaws 19 and 33 extend laterally in both directions to a sufficient eX- tentto: receive between theiny all theA runs or strands ofthesuspending rope, as willv be readily lunderstoodon 'reference tol lFig. 3, andy the'central Vportions vof the-jaws Yare bowed,asfindicatedat EST-and 38, to prevent possible contact with Vvthe ropefanchorng structure 13 on the lower pulley bloclr when the deviceis operated; 1 It will, of course,'bo understood that one outer run or strand of the suspending ropeis carried vdownwardly belowthe lower pulley block and is tied aboutthe hoolr 6 `and eye 5 so as to hold the rope :against slipping and. thereby maintain the scaffold atthe desired point. To accoininodate tlie'outerruns :of the cable `when the scaffold is.` being adjusted, l provide reinovable closures or keepers which are adapt-ed to lbridge the endsof the claniping jaws 19 and so that all the runs of the rope will beconflned between the aws;` These keepers 39v consist offsinallA plates having flanges orlips 4:0. at one :end disposed ata right angle'to their'inainfportionsand, near the saidflanges, vthe lreepers are constructed with openings through which Asecuring bolts ll/may? befvi-nserted to engage'sockets provicleclftlieiefoi.inthe ends of the jaw 33,.the flanges 40'tting against 'the' outerv side of saidtjaw, 'asV shown clearly in Fig. 3. When the .rope is being trained about ythe pulleys, these-'keepers `may' be 'removed so that the runsfor strandsof theflropeinay'be easily brought into position betweeny the jaws. iArfter Athe: yrope" has been satisfactorily trained aboutthe pulleys, the `keepers are brought into positionand `secured-'and will 'thenrestrain thesev'eral runs ofthe cables so that:` they cannotpass beyond the ends `of the jawsand assume: awpositionf'in which they cannot be engaged by the jaws. 'In the norinal position of thel parts, the free end's'of the 1 keepers: 5 will I bear lightly against .the outer-,end rvsurfaces/ofthe: jaw-19` sov that, `while'` they-will cor'npletely `bridge thel space 'between-the-jaws, they =will;n`ot interfere with the relativeniovenient ofthe saine in anywayf v n vThe sca'ifold `is' employed yand adjusted from point to :point as Ythelwork :being performed'deinandsin the usual-manner of any ordinary swinging scaffold. Normally the Vjaws i9 and 33 are out of Contact with all the strands ofthesuspending rope butare disposed close enough tofsaifd s trandsto quickly engage theni if the occasion should arise, Yalthough leaving suicient play to perinit the strands to move readily and easily in adjusting the scaold. Should the rope break at any point, the end of the seaffold supported 1 by the `broken rope obi viously at once startsite fall andthe scaffold assunie's the inclined `j'iosition shown' i'u Fig. 2. llilhen t-he end of the scaffold'drops, as justl sta-teththe connecting rod23 .follows the',inovenie-ntand inasmuch as, the movenient at the ext-renie end of'the'scafto'ld is greater than the lnoveinen't at points spaced inwardly from the end, the descent of thc connecting rod will be relatively greater and niore rapid thanthe descent ofthe pulley block Z with thepos't 14 carried thereby.` As a resulhthe lever l5 'isswung aboutits pivotal connection with the supporting post 14A, as shown in Fig, and the clamping jaw 33 is forced against vthe rope. -Thelniovenient ofthe lever is transi'nitted through the link 2l tothe jawvl9 so that said jaw is swung about its pivot l? and is thereby causedvto grip-the rope. this manner instantly carried against the opposite sides of all the strands orruns of the rope and efleotually andpositively grip the saine, as shown in; F ig. 2, so that they constitute a very strong bralreand'atonce arrestthe movement ofthe rope'so that the fall of the scaold willbearrested and injury to the workmen or possible lossof life will be avoided. l It. will be readily ing desoriptiointalten infconnection with the accompanying drawinga. that Tl have provided a very siinpleand inexpensiveapparat-us which may be ,readily applied to any swinging scaffold `and which .will operate instantly and automatically uponthebrealringof the, rope to clainpthe. rope andzprevent-r dropping ,ofthegscaifo'ldmg- Haj/ing.. thus described they what is claiined` as lnew isz..y t l 1. A. safetydevioe-for swinging scaffolds cornprisinga pair ofk jaws *disposedy at op.- posite sidesof the,scaffold-suspending rope invention,

rand normally freey thereof, a lever lcarrying said-jaws, means-for supporting said lever vfrom a pulley block of the scaffold, and

a-fconnection ,between the end Iof the lever `and the end `of the-scaffold whereby drop? ping of theend ofthe scaffold will .cause the jaws tcy gripy the suspendingrope.. j',

2. A safety! devicef for' swinging scalfolds comprising i a lever, vniieans .forv ysupporting the lever` uponl a. relatively gXed Ipart of the scaffold, a pair of clamping vjaws pivotally suspended ron said'lt-leveranddisposed The jawslQ and 33 are in 9 noted from .the lforegoat opposite sides of the scaffold-suspending rope, a connecting rod adjustably pivoted to the outer end of the lever, an anchoring device to be secured to the end of the scaffold, and a pivotal connection between said anchoring device and the lower end of the connecting rod.

3. A safety device for swinging scaffolds comprising a supporting post to be secured to a relatively fixed part of the scaffold, a lever pivotally mounted upon the upper end of said post and spanning a run of the scaffold-suspending rope and extending outwardly toward the end of the scaffold, clamping jaw pivotally mounted upon said supporting post below the lever at one side of the runs of the scaffold-suspending rope, a link connecting the inner end of said jaw with the inne-r end ofthe lever, a co-oper ating jaw pivotally suspended upon the lever at the oposite side of the runs of the scaffold-suspending rope, adjustable means for maintaining the latter jaw in fixed relation to the lever, and a connecting rod pivoted to the outer end of the lever and adapted to be pivoted to the end of the scaold.

4. A safety device for swinging scaffolds comprising a suppo-rting post to be secured to a relatively fixed part of the scaffold, a lever mounted upon said post, a clamping jaw pivoted upon said post below the lever, a connection between the lever and the said aw, a coo )eratino' 'aw dis aosed at the o 3- l s l posite side of the runs of the scaffold-sus pending rope, a lug rising from said second jaw and pivoted to the lever, a set bolt mounted in the outer end of the said jaw and bearing against the under edge of the lever, and a connecting rod pivoted to the outer end of the lever and constructed to be pivoted to the end of the scaffold.

A safety device for swinging scaffolds comprising a supporting member to be securedto a relatively fixedpart of the scaffold, a lever mounted upon the upper end of the said member, a rope-clamping jaw mounted upon said member below the lever, a connection between the lever and said jaw, a second rope-clamping jaw pivotally suspended upon the lever, a rod pivoted to the outer end of the lever and adapted at its lower end to be pivoted to the end of the scaffold, and removable keepers bridging the ends of the said clamping jaws.

6. A safety device for swinging scaifolds comprising la lever, means for supporting the lever from a relatively fixed member of the scaffold, a jaw disposed below the lever, a connection between said jaw and the lever, a second co--operating jaw pivotally suspended from the lever, and keepers bridging the ends of the said jaws and secured to the second-1nentioned jaw, said keepers being provided with flanges bearing against the outer surface of the. sec ond-mentioned jaw and having their free ends arranged in juxtaposition to and movable past the ends of the co-operating jaw.

7. A safety device for swinging scaffolds comprising a pair of opposed cooperating jaws spanning all runs of the scaffold-suspending cable and normally out of engage ment with the cable, a lever fulcrumed upon a relatively fixed part of the scaffold and connected with the jaws to move them in opposite directions, and a connecting rod attached at its upper end to the lever and at its lower end to the scaffold whereby upon dropping of the scaffold the jaws will be caused to grip the several runs of the suspending cable.

In testimony whereof I affix my signature.

ROLPH J. LACKNER. [n s] asy 

